Looper-actuating mechanism for chain-stitch sewing-machines.



0. P. GRAY. LOOPER AGTUATING MECHANISM FOR CHAIN STITCH SEWING MACHINES.

APPLICATION IILED FEB. 12, 1914.

1,127,755, V Patent aF mwm INVENTOR A TTORIVE Y WITNESSES:

'fiar/arffn pmrnp sTATEg P 1 enrich CHARLES F. GRAY, OF SIERRA MADRE,CALIFORNIA, ASQIGNOR TOTE E SING-ER MANUFACTURING COMIEANY, ACORPORATION OF NEW JERSEY.

Specification of Letters Patent.

Patented rep. a, mic.

Application filed February 12, 1914. Serial No. 818,198.

To all whom it may concern:

Be it known that 1, CHARLES F. GRAY, a citizen of the United States,residing at Sierra Madre, in the county of Los Angeles and State ofCalifornia, have invented certain new and useful Improvements inLooper-Actuating Mechanisms for Chain- Stitch Sewing- Machines, of whichthe following is a specification, reference being had therein to theaccompanying drawings. This invention relates to improvements inlooper-actuating mechanisms for chain-stitch sewing machines and has forits object to simplify and better adapt the like mechanism representedby U. S. Patent No.

Y plate and at its rear end provided with a 1,085,801 dated Feb: 3, 1914to Albert H.

De Voe, to multiple needle machines, especially such constructions asare represented by my pending application Ser. No. 817 ,7 37 filed Feb.10, 1914, for improvements in sewing machines.

The present invention, in substantially its present form, is disclosedin the pending application above referred to and for a betterunderstanding of its applicationit is herein combined with the likebed-plate, bracketarm, needle thread' take-up, under loopen actuatingshaft and cloth-feeding mechanism; omitting the tension devices, threadleaders, loop-takers and the elements connecting the latter with thelooper-actuating shaft, common to lock-stitch seam construction.

Referring to the drawings, Figure .1, is a view in front side elevationof the present machine, the frame being shown partly in section tobetter illustrate certain detailsv standard 2 and arm-bracket 3, at themain sewing machine bed-plate upon which is mounted the bracket-armcomprising the or needle-bar driving; shaft provided with the band orhand-wheel 5 and operatively connected with the lower orlooper-actuatins, shaft 6 by connections as 7.

8 denotes the feed rock-shaft mounted in suitable bearings dependingfrom the bed- 15 represents a needle-feed rook-shaft- Journaled insuitable bearings formed in the arm-bracket and at its rear end providedwith a rigidly secured crank-arm 16 to the outer end'of which ispivotally connected a needle-feed connection 17, the lower end of thelatter being pivotally connected to the crank-arm 9 and havingthe sameaxis as the lower end of the connection 10. To the forward end of theneedle-feed rock-shaft is suitablysecured a needle vibrating arm 18whose free end enters a suitable slot formed in the co-llar19 (shown indottedlines only Fig 1) carried by the needle-bar 20, thus transmittingfrom the main-shaft through the feed eccentric and connections 10, 9,1?, i6, 15, 18 and 19, feed movements to the needle 21 corresponding inamplitude to the feed movements of the feed-dog 12, and 23 denotes thecloth-.presser suitably secured to the lower end 2% of one form ofcommonly j employed cloth-Dresser carrying bar. the plate 26 secured byscrews, as 27, to the front'side of the bracket-arm and provided withthe index 28, pointer 29 and opening 30 comprises elements forming apart of the feed-adjusting mechanism, but as the latter has noparticular bearing on the present invention, further reference to itsconstructive features is deemed unnecessary.

31 represents a looper-actuating eccentric carried by the main-shaft 6and encircled by an eccentric strap or collar 32 provided with a bearing33 inclined to the plane of rotation of said eccentric, and into saidbearing is mounted the looper-carrying rod 34 provided with the looper35. the opposite end of said rod being secured by means of the pivotscrew 36 in a forked opening 3'? of the sliding sleeve 38, which latteris mounted on the pin 39 carriedby a bracket 40 secured by suitablescrews, to a stationary part of the'sewing machine frame. The providingof the pivotal connection 36 insures that the rod 34: will not be"directed out of alinement with its bearing 33 through any fault due tothe mounting of the pin 39. The looper 35 comprises a straight bladehaving the usual thread eye at itspoint, its opposite end being providedwith the thread-leader 41 through which the looper thread is passed tothe thread eye, the eccentric strap or collar 32 being confined-betweenthe flanges, as 42, carried bytheeccentric 31.

43 denotes a needle-thread loop-guard carried by the looper betweenwhich and said guard the needle rises in the formation of its threadloop, the guard acting to better insure the formation of the loop at theside of the needle next-the looper. From the foregoing it will bereadily understood that the eccentric 31 transmits to the looperneedle-thread loop-engaging and loop-shedding movements in directionstransverse to the looper-actuating shaft, and that the angularlyarranged bearing 33 acts upon the looper-carrying rod 34: to effectneedle avoiding movements of the looptaker in directions correspondingto the length of said shaft. It is not deemed necessary to herein definethe relative action of looper and its coacting needle to form stitches,as such relative action is common to earlier constructions and wellunderstood by those versed in the art, except to explain that as thelooper is moved toward the front of the machine it enters theneedle-thread loop as the needle is being moved upward, the nextsubsequent descent of the needle entering the looper-thread loop whenthe looper in its further movement in a direction away from the front ofthe machine sheds the needle-thread loop which is drawn into the fabricin the formation of the stitch,

during which time the looper has reversed -of the upward stroke of theneedle.

its motion to form a succeeding stitch, the looper being at the left ofthe needle during its forward movement and at the opposite side duringits retracted movement.

Nearly, if not all, chain-stitch stitchforming mechanisms employ aneedle-thread take-up for controlling the slack .of the thread after thelooper has entered the thread loop to substantially the completion Suchtake-up in some varieties of constructions being independent of theneedle-bar and in others effected by passing the thread through asuitable openingin the upper end ofthe needle-bar. In the presentconstruction the like control of the like thread is effected by thedownward movement of the lock stitch take-up 44: which, as is wellunderstood, effects its most important functions of controlling theformation of alockstitch seam on its upward movement when, after theloop has been cast about the under cop or bobbin, acts to control theslack of the diminishing loop, and at substantially the completion ofsuch movement acts to set the stitch. In the present construction thelock-stitch seam take-up, in connection with the thread opening 48,effects the same control of the chain-stitch needle-thread as theneedle-bar or independent take-up common to chain stitch sewing machineconstruction.

In the threading of the needle and looper the needle-thread 4:5 ispassed from the supply through the thread eye 46, tension device 47,thread opening 48 formed in the bracket 49 adjustably secured by screws,as

50, to the arm-bracket, beneath the take-up 44, through the threadopening 52, threadretaining check 53, from which'latter it is passedthrough the eye of the needle. The

looper or under chain-stitch thread 5 is passed through the tension 55,thread-check 56 to the action of the under take-up 57, then through thetubular opening 58 to the thread-leader 41 carried by the looper 35-,and through the thread 'eye 59 of said looper. The presentlooper-actuating mechanism is adapted for either the eyed or non-eyedlooper, dependent upon whether a single or double chain-stitch. isdesired. To adapt .the present looper-carrier to single or multi pleseam products, as shown by Fig. 4, the head .59 of the carrier'Z-H isprovided with a multiple of looper seats, as 60, thus etfecting astitch-forming mechanism for producing either single or multiple seamsby a single chain of connections connecting either a single looper or amultiple of the latter With the prime actuating member, as shaft 6 ofthe present construction.

Having thus set forth the nature of the invention, what I claim hereinis 1. In a stitch-forming mechanism for sewing machines, the combinationwith an upper stitch-forming mechanism and actuating means therefor, ofan under cooperating stitch-forming mechanism including a.looper-actuating shaft operatively connected with said actuating meansand carrying a looper-actuating eccentric provided with an eccentricstrap having a bearing arranged, at an angle to the plane of rotation ofsaid eccentric, a stationary bearing provided with a sliding sleeve, alooper-carrying rod mounted in said angularly arranged bearing andconnected at one end. with said sleeve and at its opposite end providedwithmeans coacting with said upper stitch-forming mechanism to formstitches.

2. In a stitch-forming mechanism for sewing machines, the combinationwith an upper stitch-forming mechanism and actuating means therefor, ofan under coopermamas a looperv-actuating vshaft operatively connectedwith said actuating means and carrying a looper-actuating eccentricprovided with an eccentric strap having a bearing arranged at an angleto the plane of rotation of said eccentric, a stationary bearingprovided with a sliding sleeve, a looper-carrying rod mounted in saidangularly arranged bearing and pivotally connected at one end with saidsleeve and at its opposite end provided with means coacting with saidupper stitch-forming mechanism to form stitches.

3. In a stitch-forming mechanism for sewing machines, the combinationwith an upper stitch-forming mechanism and actuating means therefor, ofan under cooperating stitch-forming mechanism including alooper-actuating shaft operatively connected withsaid actuating meansand carrymg a. looper-actuating eccentric provided with. an eccentricstrap'havinga bearing. arranged at an angle to the'plane of rotation ofsaid eccentric, a stationary bearing provided with a sliding sleeve, alooper-carrying rod provided with a multiple of looper securing seats,said rod beingmo'unted in said angularly. arranged bearing and connectedat one end with said sleeve and at its opposite end provided with means00- acting with said upper stitch-forming mechanism to formstitches.

In testimony whereof, I have signed my name 'to thisspecification, inthe presence of two subscribing witnesses.

5 CHARLES 1 GRAY.- Witnesses:

W L. GILLILAND, Gannon B. Moneninen.

